Yup, I mentioned this in the other thread. Hysteria and illogical thinking will make this into an incident that prevents further nuclear power construction. When it should be used as an example of how safe they truely are.
Sigh...
I read this morning in the paper that in my country an action group against nuclear energy is using the Fukushima reactor accident as proof that nuclear energy is not save. Convieniently forgetting that the biggest earthquake and tsunami in a century where not enough to cause any serious damage. Convieniently forgetting that even after failure of the cooling system there was no serious danger. Convieniently forgetting that the Sovjet RMBK reactor and the Fukushima BWR reactor are of a totally different species.
Sigh...
In memoriam: The nuclear power amplifier Carlo Rubbia (1993 - 2003)
On 24 November 1993, while still Director General of CERN, the particle physicist Carlo Rubbia creates a precedent extraordinary hustling all scientific traditions: Making use of the prestige of his Nobel Prize he spoke directly to the press and the general publicly announcing that he alone --- --- would have found a radical and definitive solution to all problems of nuclear energy. In front of several television channels and dozens of stunned reporters, he explained that his technique (he has just patented) product safe nuclear energy without radioactive waste, and without risk of proliferation of nuclear weapons.
In fact, Carlo Rubbia had to reinvent hot water, a reactor concept as old as that of existing nuclear power plants. In them the fuel is maintained in a `` critical''stable (k = 1) because the chain reaction is normally stabilized by cons and thermal-neutron reactions. The `` discovery''of Carlo Rubbia was a contribution of neutrons outside the fuel may lead to a net production of energy in a system where the fuel is, in principle, constantly in a state `` subcritical'' (k <1), which removes a priori risk of a nuclear explosion (k> 1). In theory the chain reaction stops automatically when the external source is excluded entirely, the system can be considered a `` where''amplifier power needed to run the `` source''multiplied by a factor G = 1 / (1-k), which can be very large if k is close to 1.
External source of neutrons can take a particle accelerator, for example, protons produce neutrons by spallation by hitting a target of heavy nuclei, such as lead or bismuth. This is the concept of hybrid reactor spallation-fission returned to the agenda by Carlo Rubbia. But this source could also be a thermonuclear fusion reactor, which corresponds to a hypothetical hybrid fusion-fission, or when a high-powered laser or particle of antimatter --- Another idea put forward by Carlo Rubbia. The discussion of the draft energy amplifier is therefore applicable to a range of hybrid nuclear systems, which are regularly submitted to the agenda in debates about the future of nuclear energy.
Flow diagram of rubbiatron
The reaction of the community power was not long to wait. December 9, 1993 in the influential Nucleonics Week published a reply which, ten years later, is all the more remarkable that all the criticisms proved essentially correct. Indeed, the main theoretical advantage of rubbiatron, sub-criticality is in practice a technological illusion: To operate, the system must be brought into a state of near-critical state, which means that the production of nuclear waste the risk of neutron excesses can lead to criticality accidents, waste heat to evacuate after a normal shutdown or accidental machine, etc.. are comparable to those of an ordinary reactor using the same nuclear fuel.
In a word, is not rubbiatron `` inherently safe,''including the fact that the elimination of cons-neutron reactions in favor of an external source of neutrons can easily lead to very dangerous situations, especially when the coefficient k is greater than 0.95. For this reason, it is impossible to construct a power amplifier with a gain G high (eg, k> 0.98). The `` accelerator''of the system (in theory very small if k could be close to 1) is necessarily cumbersome and costly, so the rubbiatron can not be a source of energy economically competitive.
In addition, other benefits''from `` rubbiatron proved to be equally illusory from the start: By a process not very clever but honest, Carlo Rubbia has awarded its system qualities that are not inherently related to its project hybrid reactor, but technical options such as thorium rather than uranium as fuel (which avoids the production of plutonium), or a spectrum of fast neutrons rather than heat (which can destroy some waste Nuclear). It follows that by pretending the problems solved with these techniques --- while they are still under study --- he gave the impression that its system met all the benefits of nuclear power, with minimal disadvantages.
It is therefore surprising that the proposal of Carlo Rubbia ale received a homepage so excited, as with parliamentarians and political leaders, the general public. Probably because it breathes again in a fairly depressed environment, industry and other nuclear professionals left to do ...
Thus all kinds of projects emerged, all as delusional optimism than each other. For example, for Spain, Carlo Rubbia developed a promising strategy for self-sufficiency in power and total elimination of waste in a few decades. The demonstration was to be made ​​in the state of Aragon, where a private company with government participation (LAES, Laboratorio del Amplificador Energie SA, English `` European Laboratory for the Energy Amplifier'') was created. At the height of a political and media hype unheard of, which even saw the unexpected participation of the Nobel Prize Georges Charpak, Professor Juan Antonio Rubio of the University of Zaragoza announced April 27, 1997 in Aragon di Heraldo: `` A prototype 100 - 250 MW in 2002!''In fact, the bankruptcy of LAES was quietly announced September 27, 2001 in El Mundo, while over two years there had been more contact between LAES and Carlo Rubbia ...
Meanwhile, the group Rubbia at CERN produced a dozen reports, all as optimistic as each other, especially with major scientific advances as the results of simple experiments such as FEAT and TARC (who tested that thing --- we already knew --- that since 1950 under conditions favorable energy production and transmutation of nuclear waste were possible with an accelerator). But it was a flash in the pan, the last substantial publications dating back to 1998 - 99. Since then, the only activity related to the CERN rubbiatron is the experience nTOF measuring cross sections in areas of energy and precision to date were only available to members.
An important step was the rubbiatron a hearing open to the press by the Parliamentary Office for Evaluation of Scientific and Technological. Chaired by Claude Birraux the hearing of November 21, 1995 recalls the theoretical advantages of the concept, developed the criticism since 1993, and focused on security issues and links with the proliferation of nuclear weapons.
Thus the audience was surprised to see how Carlo Rubbia was `` naive''about the risks of diversion to military purposes of its system, while it is easy to verify that a single production accelerator medical isotopes can be used to produce significant quantities of plutonium or tritium. In addition, by using some basic tips, for example by irradiating a sample of enriched uranium, one can easily increase tenfold the production of a small neutron accelerator, and so transform 1 kg of U-235 in 10 kg plutonium! It is precisely on such a system which worked then Yugoslav scientists lab Vinca near Belgrade, a system developed in collaboration with scientists associated with CERN, and controlled by a scientific committee chaired by a former head of divisions CERN, Gunther Plass. The adventure ended on the night of 21 to 22 August 2002, when the IAEA inspectors, supervised by the U.S. army, seized at Vinca all enriched uranium that was there (48 kg, which up to 400 kg of plutonium). This action violates international law, as an act of `` preventive war''by the United States, is now considered a historical turning point. Indeed, even before the invasion of Iraq, it was followed by the North Koreans' decision to publicly announce the resumption of their nuclear weapons program (which, it must be remembered, pales before the capacity of South Koreans in this field, who are already studying a spallation-fission hybrid, according to them ideal for waste transmutation, but equally good for any production of tritium).
Regarding security, the discussion abounded on the weaknesses of rubbiatron: The interface between the accelerator and the reactor, ie the window that separates the vacuum tungsten molten lead. In particular, detailed calculations carried out by Jacques Maillard and his PhD student Fabienne Bacha showed that such a window could be broken after a few hours because of the intense bombardment by accelerated protons. It took until the first experience is both unrealistic, experience Lisors the Paul Scherrer Institut (PSI) near Zurich, to verify that their prediction was correct. On July 5, 2002, after 36 hours of irradiation at full power, the window is split, and a jet of molten lead-bismuth watered slightly radioactive apparatus. Scientists and direction of the PSI tried to remain silent on this `` incident''and it took my personal intervention for some technical details are published in January 2003.
Obviously, Carlo Rubbia had long found the solution to avoid problems of window, just simply remove the. It is the right option for the latest project of amplifier power is still alive, based on a design developed by the Italian company Ansaldo Nucleare, where survivors of the group Rubbia at CERN have made ​​some calculations of neutron. But if the window is excluded entirely, that containment is broken! And pump residual vapors is wanting to capture and process online highly toxic polonium-210 is produced when protons or neutrons bombard a mixture of lead-bismuth ...
Today, with the exception of the demonstration project sponsored by Ansaldo Nucleare and some experiments at the TRIGA research reactor in Italy, and one or two theoretical studies funded by the European Commission, we can say that the amplifier Energy is dead. Carlo Rubbia has regained its role as the locomotive of large projects, both chairman of the Working Group of the European Commission on nuclear systems driven by accelerators (TWG22) and spokesperson of an experiment of fundamental physics with neutrinos ( ICARUS). Certainly, there are experiences like Lisors, and its sequel MEGAPIE who develop components or processes that might have been part of a rubbiatron. But these are mainly developed for possible transmutation of nuclear waste, or production of special nuclear material at the end of military medical or using particle accelerators.
In conclusion, the rise and fall of the proposed energy amplifier Carlo Rubbia is an important event that deserves a detailed analysis by sociologists and historians of science. It is indeed an event that illustrates the dysfunctional leisure science system (where a leader can lead his peers on the wrong track without ever having to be accountable), media (where the prestige of a Nobel Prize leads to a blind adulation), politics (where elected officials are easily manipulated by strong personalities), large institutions (where the mandarins have more weight than objective arguments), that human society tout court (where honest workers and scientific integrity are crushed by the ambitions of the great chefs). Nevertheless, it is gratifying that some valves have functioned, for example the parliamentary hearing chaired by Claude Birraux, or the courage of some individual scientists who took it upon themselves to stand up to a Nobel particularly representative of a scientific world dominated by the pursuit of power in all its forms.
Andre Gsponer
Sigh...
I read this morning in the paper that in my country an action group against nuclear energy is using the Fukushima reactor accident as proof that nuclear energy is not save. Convieniently forgetting that the biggest earthquake and tsunami in a century where not enough to cause any serious damage. Convieniently forgetting that even after failure of the cooling system there was no serious danger. Convieniently forgetting that the Sovjet RMBK reactor and the Fukushima BWR reactor are of a totally different species.
Sigh...
Heh...I'd wager by your reasoning anything below a 7 nuclear event is not serious damage. You are a prime example of the irresponsibility of the pro-nuclear crowd. Nuclear safety goes far, FAR BEYOND the external integrity of a containment vessel and there is no chance in hell you guys can hide this heap of shit, coming out of your precious tech's arse, under the rug. For now, I suggest you take your well deserved beating and shut up. There'll be plenty of time to try to sell your "clean" nuke pipe dream AFTER this thing settles.
Heh...I'd wager by your reasoning anything below a 7 nuclear event is not serious damage. You are a prime example of the irresponsibility of the pro-nuclear crowd. Nuclear safety goes far, FAR BEYOND the external integrity of a containment vessel and there is no chance in hell you guys can hide this heap of shit, coming out of your precious tech's arse, under the rug. For now, I suggest you take your well deserved beating and shut up. There'll be plenty of time to try to sell your "clean" nuke pipe dream AFTER this thing settles.
Heh...I'd wager by your reasoning anything below a 7 nuclear event is not serious damage. You are a prime example of the irresponsibility of the pro-nuclear crowd. Nuclear safety goes far, FAR BEYOND the external integrity of a containment vessel and there is no chance in hell you guys can hide this heap of shit, coming out of your precious tech's arse, under the rug. For now, I suggest you take your well deserved beating and shut up. There'll be plenty of time to try to sell your "clean" nuke pipe dream AFTER this thing settles.
So are you going to actually go into the science backing your claims here? The "pro-nuclear" crowd explained their side pretty well with great articles and diagrams. I'd love to hear the other side, but as of yet all I've seen from that is the same tired paranoia (based in complete ignorance) as always has existed about nuclear power.
Heh...I'd wager by your reasoning anything below a 7 nuclear event is not serious damage. You are a prime example of the irresponsibility of the pro-nuclear crowd. Nuclear safety goes far, FAR BEYOND the external integrity of a containment vessel and there is no chance in hell you guys can hide this heap of shit, coming out of your precious tech's arse, under the rug. For now, I suggest you take your well deserved beating and shut up. There'll be plenty of time to try to sell your "clean" nuke pipe dream AFTER this thing settles.
Heh...I'd wager by your reasoning anything below a 7 nuclear event is not serious damage. You are a prime example of the irresponsibility of the pro-nuclear crowd. Nuclear safety goes far, FAR BEYOND the external integrity of a containment vessel and there is no chance in hell you guys can hide this heap of shit, coming out of your precious tech's arse, under the rug. For now, I suggest you take your well deserved beating and shut up. There'll be plenty of time to try to sell your "clean" nuke pipe dream AFTER this thing settles.
Reuters is reporting that the risk of disaster is going down quickly and that the reactors have cooled by over 90% now.
http://www.reuters.com/article/2011/03/14/japan-nuclear-radiation-risk-idUSLDE72D19720110314
Looks no serious release of radiation is going to happen. Unfortunately, even if no real damage comes of this event, the possible use of nuclear power (at least in the US) has probably be set back decades yet again due to irrationality and poorly informed people.
Paranoia is to watch a nuclear plant blowing up and still deny the seriousness of the damage.
Oh, and here's your fucking science: *slapping it in your face*
25-26 April 1986
Engineers on the evening shift at Chernobyl's number four reactor began an experiment to see whether the cooling pump system could still function using power generated from the reactor under low power should the auxiliary electricity supply fail.
At 2300 control rods, which regulate the fission process in a nuclear reactor by absorbing neutrons and slowing the chain reaction, were lowered to reduce output to about 20% of normal output required for the test.
However, too many rods were lowered and output dropped too quickly, resulting in an almost complete shutdown.
Safety systems disabled
Concerned by possible instability, engineers began to raise the rods to increase output. At 0030 the decision was taken to carry on.
By 0100 power was still only at about 7%, so more rods were raised. The automatic shutdown system was disabled to allow the reactor to continue working under low power conditions.
The engineers continued to raise rods. By 0123, power had reached 12% and the test began. But seconds later, power levels suddenly surged to dangerous levels.
Overheating
The reactor began to overheat and its water coolant started to turn to steam.
At this point it is thought that all but six control rods had been removed from the reactor core - the minimum safe operating number was considered to be 30.
The emergency shutdown button was pressed. Control rods started to enter the core, but their reinsertion from the top displaced coolant and concentrated reactivity in the lower core.
Explosions
With power at roughly 100 times normal, fuel pellets in the core began to explode, rupturing the fuel channels.
At about 0124, two explosions occurred, causing the reactor's dome-shaped roof to be blown off and the contents to erupt outwards.
As air was sucked in to the shattered reactor, it ignited flammable carbon monoxide gas causing a reactor fire which burned for nine days.
Because the reactor was not housed in a reinforced concrete shell, as is standard practice in most countries, the building sustained severe damage and large amounts of radioactive debris escaped into the atmosphere.
Firefighters crawled onto the roof of the reactor building to fight the blaze while helicopters dropped sand and lead in an effort to quell the radiation.
Paranoia is to watch a nuclear plant blowing up and still deny the seriousness of the damage.
Oh, and here's your fucking science: *slapping it in your face*
Once again my points are proven. You amuse me. While i just explain the problems you come up with an emotional response with empty words.
There is so much hot air coming out of your mouth, that i am sure that your head must be empty to account for the excess of hot air.
Although i am just an amateur, i think the research must be done in the following (Assuming the standard model for a minute) :
The problem is that neutrons are for as far as i know not susceptible to electric and magnetic fields. Thus it is difficult to create a proper shielding besides using the only way known : Very thick walls of the toughest materials.
The research must be done into scintillation and into neutron moderation. Gamma rays ( I always get confused, but i mean the EM version) and high energy xrays can be captured and by the process of scintillation can be lowered in energy to be used for the creation of electricity. For example just as solar panels do now with the visible light spectrum and i believe some part of the uv spectrum but instead use shorter wavelength EM (photons). Of course what we want is a more advanced material that can absorb higher energy EM radiation and turn it into electricity.
The other and the biggest issue are fast neutrons. These are the dangerous ones because these do not only cause ionizing radiation but also create isotopes which themselves produces radiation ( I think it was alpha and beta decay and something else). There must be more research done where neutrons are slowed down and captured long enough to not create isotopes but to create a situation that these neutrons can decay into electrons (preferred) or positrons. Usually both are created and gamma ray EM will be the result because of the annihilation of electron-positron. And when we have EM radiation , we can use scintillation to lower the energy and then use that energy.
So you see, the problem is not that difficult to understand. The difficulty is to create the technology to be able to do this. And mindless people like you prevent research into these fields.
Do not fear what you do not know, try to understand it.
Then you know why you must fear it and be cautious.
HAHAHAHA! #1: Did you misplace your retort on the "serious damage" thing?
HAHAHAHA! #2: Nice uncharted territory you got on your sights there man. Any idea how's that going to make nuclear waste disappear?
What blew up? The building surrounding the containment building? That is like claiming your car exploded because the hood came off.
Hmmm. But I thought nuclear reactors didn't need any backup systems or interventions to shut them down in the event of a failure. But they had to fly in batteries to power the cooling system to prevent meltdown. Hmmm.... That's unlike every other power source, which can be left alone and will simply shut down with time, which is a good thing considering the possibility of some kind of EMP attack, war, or apocalyptic epidemic. What else do you nuclear proponents lie about?
And there are practically zero similarities between the Fukushima reactor and Chernobyl. Stop fear-mongering.When the Chernobil reactor overheated there was an explosion and the reactor blew through the roof and landed in a nearby forest. Then a large area is considered to be contaminated for the next 300 years.
Be afraid, be very afraid!
They had to use soldiers and volunteers to seal the reactor with cement, all of who died due to radiation exposure.
So do you have a retort or not?
A positive void coefficient means that the reactivity increases as the void content inside the reactor increases due to increased boiling or loss of coolant; for example, if the coolant acts as a neutron absorber. If the void coefficient is large enough and control systems do not respond quickly enough, this can form a positive feedback loop which can quickly boil all the coolant in the reactor. This happened in the Chernobyl disaster. The construction of reactors with a positive void coefficient is illegal in the United States.
Reactor designs
Boiling water reactors generally have negative void coefficients, and in normal operation the negative void coefficient allows reactor power to be adjusted by changing the rate of water flow through the core. However, the negative void coefficient can cause an unplanned reactor power increase in events (such as sudden closure of a steamline valve) where the reactor pressure is suddenly increased. In addition, the negative void coefficient can result in power oscillations in the event of a sudden reduction in core flow, such as might be caused by a recirculation pump failure. Boiling water reactors are designed to ensure that the rate of pressure rise from a sudden steamline valve closure is limited to acceptable values, and they include multiple safety systems designed to ensure that any sudden reactor power increases or unstable power oscillations are terminated before fuel or piping damage can occur.
Pressurized water reactors operate with no voids at all, and the water serves as both moderator and coolant. Thus a large negative void coefficient ensures that if the water boils or is lost the power output will drop.
CANDU reactors have positive void coefficients that are small enough that the control systems can easily respond to boiling coolant before the reactor reaches dangerous temperatures (see References).
RBMK reactors, such as the reactors at Chernobyl, have a dangerously high positive void coefficient. This was necessary for the reactor to run on unenriched uranium and to require no heavy water. Before the Chernobyl accident these reactors had a positive void coefficient of 4.7 beta and after the accident that was lowered to 0.7 beta. This was done so all RBMK reactors could resume safe operating and produce much needed power for the then USSR and its satellites.
Fast breeder reactors do not use moderators, since they run on fast neutrons, but the coolant (often lead or sodium) may serve as a neutron absorber and reflector.
Magnox reactors, advanced gas-cooled reactors and pebble bed reactors are gas-cooled and so void coefficients are not an issue. In fact, some can be designed so that total loss of coolant does not cause core meltdown even in the absence of active control systems. As with any reactor design, loss of coolant is only one of many possible failures that could potentially lead to an accident. In case of accidental ingress of liquid water into the core of pebble bed reactors a positive void coefficient may occur.
So are you going to actually go into the science backing your claims here? The "pro-nuclear" crowd explained their side pretty well with great articles and diagrams. I'd love to hear the other side, but as of yet all I've seen from that is the same tired paranoia (based in complete ignorance) as always has existed about nuclear power.
i also don't think the reactors were damaged in the earthquake, this issues are due to the failure of the auxiliary systems (ie emergency reactor cooling). As long as the emergency cooling water pumps run and cool down the reactor there would be no meltdown after a scram.
Everything I've heard has said the reactors DID shut down (scram) automatically when the quake struck. However, even when shut down there is a minimum amount of cooling required. They had a battery backup to their diesel generator backup. Unfortunately the battery power was insufficient to last until another power source (more generators, more batteries etc) could be acquired.
I think before panicing/passing judgement it would be a good idea to wait and get more info on exactly what happened. E.g., what damage did the quake cause to the facility? So far, it appears the facility/structure withstood the 9.0 quake; which if true would be impressive. What damage did the tsunami cause? So far it appears only to have damaged the diesel generator backups. Not good, but if the facility itself withstood the tsunami that would also be impressive. However, this seems to me to illustrate a plannig/risk management flaw; tsunami's are not unknown to Japan. A tsunami could be expected to cause a general power failure, so to depend upon backups also subject to disruption by tsunami's strikes me poor contigency planning. Finally, if the containment structures were able to withstand a (partial) meltdown (as has been reported) even after suffering an earthquake and tsunami that would also be very positive.
But I've had a concern I haven't seen raised elsewhere (could be in this thread, haven't read every post) - if they are using seawater to cool the reactor, and it's contaminated, where is iting disposed of? Are they putting contaminated seawater back into the ocean?
Fern